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Bone & Joint Research
Vol. 2, Issue 1 | Pages 1 - 8
1 Jan 2013
Costa AJ Lustig S Scholes CJ Balestro J Fatima M Parker DA

Objectives. There remains a lack of data on the reliability of methods to estimate tibial coverage achieved during total knee replacement. In order to address this gap, the intra- and interobserver reliability of a three-dimensional (3D) digital templating method was assessed with one symmetric and one asymmetric prosthesis design. Methods. A total of 120 template procedures were performed according to specific rotational and over-hang criteria by three observers at time zero and again two weeks later. Total and sub-region coverage were calculated and the reliability of the templating and measurement method was evaluated. Results. Excellent intra- and interobserver reliability was observed for total coverage, when minimal component overhang (intraclass correlation coefficient (ICC) = 0.87) or no component overhang (ICC = 0.92) was permitted, regardless of rotational restrictions. Conclusions. Measurement of tibial coverage can be reliable using the templating method described even if the rotational axis selected still has a minor influence


Bone & Joint Research
Vol. 5, Issue 7 | Pages 294 - 300
1 Jul 2016
Nishioka H Nakamura E Hirose J Okamoto N Yamabe S Mizuta H

Objectives. The purpose of this study was to clarify the appearance of the reparative tissue on the articular surface and to analyse the properties of the reparative tissue after hemicallotasis osteotomy (HCO) using MRI T1ρ and T2 mapping. Methods. Coronal T1ρ and T2 mapping and three-dimensional gradient-echo images were obtained from 20 subjects with medial knee osteoarthritis. We set the regions of interest (ROIs) on the full-thickness cartilage of the medial femoral condyle (MFC) and medial tibial plateau (MTP) of the knee and measured the cartilage thickness (mm) and T1ρ and T2 relaxation times (ms). Statistical analysis of time-dependent changes in the cartilage thickness and the T1ρ and T2 relaxation times was performed using one-way analysis of variance, and Scheffe’s test was employed for post hoc multiple comparison. Results. The cartilage-like repair tissue appeared on the cartilage surface of the medial compartment post-operatively, and the cartilage thickness showed a significant increase between the pre-operative and one-year post-operative time points (MFC; p = 0.003, MTP; p < 0.001). The T1ρ values of the cartilage-like repair tissue showed no difference over time, however, the T2 values showed a significant decrease between the pre-operative and one-year post-operative time points (MFC; p = 0.004, MTP; p = 0.040). Conclusion. This study clarified that the fibrocartilage-like repair tissue appeared on the articular surface of the medial compartment after HCO as evidenced by MRI T1ρ and T2 mapping. Cite this article: H. Nishioka, E. Nakamura, J. Hirose, N. Okamoto, S. Yamabe, H. Mizuta. MRI T1ρ and T2 mapping for the assessment of articular cartilage changes in patients with medial knee osteoarthritis after hemicallotasis osteotomy. Bone Joint Res 2016;5:294–300. DOI: 10.1302/2046-3758.57.BJR-2016-0057.R1


Bone & Joint Research
Vol. 1, Issue 10 | Pages 263 - 271
1 Oct 2012
Sharma GB Saevarsson SK Amiri S Montgomery S Ramm H Lichti DD Lieck R Zachow S Anglin C

Objectives. Numerous complications following total knee replacement (TKR) relate to the patellofemoral (PF) joint, including pain and patellar maltracking, yet the options for in vivo imaging of the PF joint are limited, especially after TKR. We propose a novel sequential biplane radiological method that permits accurate tracking of the PF and tibiofemoral (TF) joints throughout the range of movement under weightbearing, and test it in knees pre- and post-arthroplasty. Methods. A total of three knees with end-stage osteoarthritis and three knees that had undergone TKR at more than one year’s follow-up were investigated. In each knee, sequential biplane radiological images were acquired from the sagittal direction (i.e. horizontal X-ray source and 10° below horizontal) for a sequence of eight flexion angles. Three-dimensional implant or bone models were matched to the biplane images to compute the six degrees of freedom of PF tracking and TF kinematics, and other clinical measures. Results. The mean and standard deviation for the six degrees of freedom of PF tracking and TF kinematics were computed. TF and PF kinematics were highly accurate (< 0.9 mm, < 0.6°) and repeatable. Conclusions. The developed method permitted measuring of in vivo PF tracking and TF kinematics before and after TKR throughout the range of movement. This method could be a useful tool for investigating differences between cohorts of patients (e.g., with and without pain) impacting clinical decision-making regarding surgical technique, revision surgery or implant design


Bone & Joint Research
Vol. 6, Issue 1 | Pages 31 - 42
1 Jan 2017
Kang K Koh Y Jung M Nam J Son J Lee Y Kim S Kim S

Objectives

The aim of the current study was to analyse the effects of posterior cruciate ligament (PCL) deficiency on forces of the posterolateral corner structure and on tibiofemoral (TF) and patellofemoral (PF) contact force under dynamic-loading conditions.

Methods

A subject-specific knee model was validated using a passive flexion experiment, electromyography data, muscle activation, and previous experimental studies. The simulation was performed on the musculoskeletal models with and without PCL deficiency using a novel force-dependent kinematics method under gait- and squat-loading conditions, followed by probabilistic analysis for material uncertain to be considered.


Bone & Joint Research
Vol. 5, Issue 3 | Pages 80 - 86
1 Mar 2016
Scott G Imam MA Eifert A Freeman MAR Pinskerova V Field RE Skinner J Banks SA

Objectives

Throughout the 20th Century, it has been postulated that the knee moves on the basis of a four-bar link mechanism composed of the cruciate ligaments, the femur and the tibia. As a consequence, the femur has been thought to roll back with flexion, and total knee arthroplasty (TKA) prostheses have been designed on this basis. Recent work, however, has proposed that at a position of between 0° and 120° the medial femoral condyle does not move anteroposteriorly whereas the lateral femoral condyle tends, but is not obliged, to roll back – a combination of movements which equates to tibial internal/ femoral external rotation with flexion. The aim of this paper was to assess if the articular geometry of the GMK Sphere TKA could recreate the natural knee movements in situ/in vivo.

Methods

The pattern of knee movement was studied in 15 patients (six male: nine female; one male with bilateral TKAs) with 16 GMK Sphere implants, at a mean age of 66 years (53 to 76) with a mean BMI of 30 kg/m2 (20 to 35). The motions of all 16 knees were observed using pulsed fluoroscopy during a number of weight-bearing and non-weight-bearing static and dynamic activities.


Bone & Joint Research
Vol. 3, Issue 10 | Pages 289 - 296
1 Oct 2014
van IJsseldijk EA Harman MK Luetzner J Valstar ER Stoel BC Nelissen RGHH Kaptein BL

Introduction

Wear of polyethylene inserts plays an important role in failure of total knee replacement and can be monitored in vivo by measuring the minimum joint space width in anteroposterior radiographs. The objective of this retrospective cross-sectional study was to compare the accuracy and precision of a new model-based method with the conventional method by analysing the difference between the minimum joint space width measurements and the actual thickness of retrieved polyethylene tibial inserts.

Method

Before revision, the minimum joint space width values and their locations on the insert were measured in 15 fully weight-bearing radiographs. These measurements were compared with the actual minimum thickness values and locations of the retrieved tibial inserts after revision.


Bone & Joint Research
Vol. 2, Issue 2 | Pages 18 - 25
1 Feb 2013
Kon E Filardo G Di Matteo B Perdisa F Marcacci M

Objectives

Matrix-assisted autologous chondrocyte transplantation (MACT) has been developed and applied in the clinical practice in the last decade to overcome most of the disadvantages of the first generation procedures. The purpose of this systematic review is to document and analyse the available literature on the results of MACT in the treatment of chondral and osteochondral lesions of the knee.

Methods

All studies published in English addressing MACT procedures were identified, including those that fulfilled the following criteria: 1) level I-IV evidence, 2) measures of functional or clinical outcome, 3) outcome related to cartilage lesions of the knee cartilage.


Bone & Joint Research
Vol. 1, Issue 12 | Pages 315 - 323
1 Dec 2012
Molt M Ljung P Toksvig-Larsen S

Objectives

The objective of this study was to compare the early migration characteristics and functional outcome of the Triathlon cemented knee prosthesis with its predecessor, the Duracon cemented knee prosthesis (both Stryker).

Methods

A total 60 patients were prospectively randomised and tibial component migration was measured by radiostereometric analysis (RSA) at three months, one year and two years; clinical outcome was measured by the American Knee Society score and the Knee Osteoarthritis and Injury Outcome Score.


Bone & Joint Research
Vol. 1, Issue 8 | Pages 167 - 173
1 Aug 2012
Jack CM Rajaratnam SS Khan HO Keast-Butler O Butler-Manuel PA Heatley FW

Objectives

To assess the effectiveness of a modified tibial tubercle osteotomy as a treatment for arthroscopically diagnosed chondromalacia patellae.

Methods

A total of 47 consecutive patients (51 knees) with arthroscopically proven chondromalacia, who had failed conservative management, underwent a modified Fulkerson tibial tubercle osteotomy. The mean age was 34.4 years (19.6 to 52.2). Pre-operatively, none of the patients exhibited signs of patellar maltracking or instability in association with their anterior knee pain. The minimum follow-up for the study was five years (mean 72.6 months (62 to 118)), with only one patient lost to follow-up.